Cannot build from CVS under Cygwin

While trying to add my $0.02 to the discussion on GTK, pdump and Cygwin/NT, I discovered that I have a more basic problem in building in a tree freshly checked out from CVS. The build hangs at the dump-elcs step as soon as temacs starts to byte compile the first lisp file. The temacs is running: ./temacs -nd -batch -l /cygdrive/c/Xemacsdevel/r21-2-44/src/../lisp/update-elc.el and gets as far as: Bootstrapping from temacs... Static heap usage: 4551252 of 8650752 -- 4003k wasted Compiling /cygdrive/c/Xemacsdevel/r21-2-44/lisp/auto-autoloads.el And then it hangs. I've tried to bring up temacs using the run-temacs command line, but that fails because it cannot find ../lib-src/DOC. It is not possible to attach to the looping temacs and learn anything. david